Bunsen burners at the ready, it's back to the lab again with Mercury Meltdown on PSP.

Archer Maclean's Mercury was one of the standout launch titles for PSP. Moving a blob of mercury around a three dimensional maze whilst avoiding mercury-eating monsters and the ever-present edge proved to be ridiculously fun, as Mercury combined platforming with puzzling in a way that perfectly suited the handheld format. It didn't go unnoticed either, making the game a hit with critics and the public alike. So it was only a matter of time until a sequel showed up, and from what we've seen, it looks like it's going to be great.

For the most part the developers have chosen not to tamper too much with a winning formula. The goal remains to get as much of your mercury as possible to the goal, negotiating tricky puzzles and mazes along the way. However there have been a few tweaks to make the whole experience a vast improvement on the already impressive original.

The first and most obvious difference is the visual style. Moving away from Mercury's realistic graphics, Mercury Meltdown takes a new direction with a cartoony art style that suits the '50s science fiction theme perfectly.

Also new for Mercury Meltdown are a variety of new additions to help you reach the goal. There are different kinds of surfaces on the levels now, ranging from sticky floors that slow your mercury down, to slippery floors that speed you up, but make control a lot harder.

There are also new objects, like your friendly pal Stan, a smiley face contained within a squishy block that you can direct around the mazes and use to activate switches. Also new is the Huebrick, a coloured brick that you can move around the level by colliding with it, and is essential to completing some of the fiendish puzzles spread across the game's 160 plus levels.

From what we've seen so far it looks like Mercury Meltdown could be the perfect sequel; keeping everything we loved about the original, and improving on its weaknesses in a fun and innovative way. Keep your lab goggles trained on yourpsp.com for a Playtest as soon as we get our hands on a copy.